263086981 has 2 divisors, whose sum is σ = 263086982. Its totient is φ = 263086980.

The previous prime is 263086979. The next prime is 263086997. The reversal of 263086981 is 189680362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211964481 + 51122500 = 14559^2 + 7150^2 .

It is a cyclic number.

It is not a de Polignac number, because 263086981 - 2¹ = 263086979 is a prime.

It is a super-2 number, since 2×263086981² = 138429519143388722, which contains 22 as substring.

Together with 263086979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (263086081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131543490 + 131543491.

It is an arithmetic number, because the mean of its divisors is an integer number (131543491).

Almost surely, 2^263086981 is an apocalyptic number.

It is an amenable number.

263086981 is a deficient number, since it is larger than the sum of its proper divisors (1).

263086981 is an equidigital number, since it uses as much as digits as its factorization.

263086981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 263086981 is about 16219.9562576476. The cubic root of 263086981 is about 640.7664815765.

The spelling of 263086981 in words is "two hundred sixty-three million, eighty-six thousand, nine hundred eighty-one".